[tymoto99]

I've been trying to understand why motorcycles sometimes have a "clunk" when shifting to 1st gear from neutral while stationary. People tend to say it's normal. In fact, all my past motorcycles did this. I'm curious as to why though. I perceive the clunk as a rough/agressive engagement of the gear internally, so I'm not sure if I should be trying to minimize it. If it was harmful, I imagine the manufacturers wouldn't have engineered it that way. However I've ridden a friend's 2009 CBR 600RR and it had no clunking.

Here are the patterns I've observed:
1. Upon start up, motorcycle is in neutral. I get on the bike, pull in clutch lever, shift to 1st. This shift causes loud clunk (like metal snapping into place, which is exactly what's happening internally)
2. Upon start up, motorcycle is in neutral. I get on the bike and it's on an incline facing downhill. I hold the clutch lever in, let the incline take the bike forward a bit before shifting. No clunk, butter smooth feeling/sounding shift to 1st gear

Patterns also vary when I'm in motion depending on my speed but I'll try to keep this short for now.

Apparently Harley Davidson engineered their bikes to have the "clunk" because their fan-base prefers that sound of the gear engagement.

Does your motorcycle clunk into first gear? I've somewhat accepted it's a characteristic of motorcycles but I'm still curious.

 

[tymoto99]

Found some explanation for it here: https://www.reddit.com/r/motorcycles/comments/6938ot/sportbikes_is_a_clunk_into_first_gear_normal/


"Yes. If its in N with no clutch input, all the transmission gears are turning. When you apply clutch the whole thing keeps turning anyway, and it clunks when the dogs on 1st engage.

Try this, put it in N and idle without touching the clutch. Shift into 1st. It will clunk loudly.

Next, shift back into N. Now hold the clutch for a few seconds, then shift into 1st. The clunk will be a lot quieter.

TL;DR its supposed to do that, because of the way motorcycle transmissions work. It will only not do that if the engine is off."